How should I approach the initial screening and genetic testing for patients suspected of having familial hypercholesterolaemia?

For initial screening, healthcare professionals should suspect familial hypercholesterolaemia (FH) in adults with a total cholesterol level greater than 7.5 mmol/l or with a personal or family history of premature coronary heart disease (before age 60 in an index individual or first-degree relative) ¹.

Systematic search of primary care records should be conducted for people younger than 30 years with a total cholesterol greater than 7.5 mmol/l, and for those 30 years or older with a total cholesterol greater than 9.0 mmol/l, as these groups are at highest risk of FH ¹.

Before considering a diagnosis of FH, secondary causes of hypercholesterolaemia should be excluded, such as hypothyroidism, liver disease, nephrotic syndrome, and uncontrolled diabetes ¹.

Use clinical criteria such as the Simon Broome or Dutch Lipid Clinic Network (DLCN) criteria to make a clinical diagnosis of FH in primary care settings, performed by a healthcare professional competent in using these criteria ¹.

If the patient meets the criteria for possible or definite FH (e.g., DLCN score >5 or meeting Simon Broome criteria), they should be referred to an FH specialist service for DNA testing ¹.

Initial genetic testing involves DNA analysis for known disease-causing mutations in the LDL receptor gene or other related genes, following specialist referral ¹.